SAN JUAN, Puerto Rico -- More than 1,000 journalists have visited Guantanamo Bay since the U.S. military began locking up suspected al-Qaida and Taliban militants there 4 1/2 years ago. But access has been severely restricted: Journalists could not talk to detainees, they had to be accompanied by a military escort and their photos were censored.

Now, the Pentagon has shut down access entirely _ at least temporarily _ expelling reporters this week and triggering an outcry from human rights groups, attorneys and media organizations even as the prison comes under renewed criticism for the suicides of three detainees last weekend.

"Now is the time when the media is most needed," said Clive Stafford Smith, an attorney who has filed legal challenges on behalf of about 40 detainees. "The fact that right now, the most important time in the history of Guantanamo, they are being banned is un-American."

Pentagon officials defended the temporary ban on media, saying guards and base officials are preoccupied with investigating the deaths and maintaining security as detainees become more defiant. A clash with guards in May left six detainees injured. Another 10 prisoners were on hunger strike Thursday, including six being force-fed with nasal tubes.

U.S. officials say the Guantanamo Bay Naval Base, which sits on cactus-studded hills in southeastern Cuba overlooking the Caribbean and mangrove forests, has been unusually open to journalists _ despite media complaints that access while they are at the prison is severely curtailed and requests for interviews often vanish in the military bureaucracy.

But the Pentagon rejected all requests by news organizations this week to cover the investigation and aftermath of the suicides, the first detainee deaths since Guantanamo opened.

About 10 news organizations, including The Associated Press, were to cover a military tribunal this week for one of the 10 detainees charged with crimes. But the hearing was postponed and hours before they were to depart for Guantanamo, the Pentagon canceled the authorizations that reporters need to visit.

Reporters cover the hearings from the courtroom _ where they are barred from speaking with participants, even during breaks. Or they can view the proceedings on a large-screen TV near a media center where military censors peer at their photographs and video and decide what is out of bounds.

On Wednesday, the Pentagon expelled two journalists _ from the Los Angeles Times and The Miami Herald _ who arrived at Guantanamo on a charter flight Sunday and two others from The Charlotte Observer, who were at the base for coverage of a commander from North Carolina.

The Paris-based group Reporters Without Borders said Thursday the expulsions damage the credibility of the U.S. government.

"We condemn the Pentagon decision and we call on the U.S. government to take the necessary steps to guarantee the media free access to the naval base at Guantanamo," the group said.

Media visits have been common, drawing journalists from dozens of countries, but they have always come with thick strings attached.

Access to the base is available only through military planes or small charters. The charters take about 3 hours to fly from Florida to Guantanamo because they can't travel through Cuban airspace and must circle around the island.

On the base, a 10-page list of ground rules bars journalists from interviewing anyone without approval and prohibits photos of detainee faces and base features, such as radar or the coastline. The military says such restrictions are needed for security and to protect detainees' privacy.

But critics say the military is being disingenuous in saying it wants to protect detainees' privacy. One prisoner, speaking in English, once told a visiting AP reporter that he wanted to talk. But when the reporter asked the military if she could interview the detainee, the answer was no.

Other reporters have been have been hustled away when prisoners have tried to communicate with them _ through food slots in the cells of the highest-security section, or from behind curtains at the medical clinic.

Gordon said regular media access is scheduled to resume next week, with journalists from three European news organizations taking a tour that can take two months or more to arrange.

But without access to the detainees, Stafford Smith said such visits amount to little more than propaganda.